In mice, the A allele causes agouti fur, the AY allele causes yellow fur and is dominant to the A allele. The homozygous AY AY genotype is lethal. Why is the AYAY homozygous condition lethal? The AY allele highly transcribes the merc gene which is lethal in a homozygous AYAY individual. None of the other answers are correct. The AY allele lacks an upstream merc gene which is required for normal embryonic development. The AY allele contains a null mutation in the A gene, which is required for normal embryonic development. The yellow pigment produced by A allele is required for survival.

In mice, the A allele causes agouti fur, the AY allele causes yellow fur and is dominant to the A allele. The homozygous AY AY genotype is lethal. Why is the AYAY homozygous condition lethal? The AY allele highly transcribes the merc gene which is lethal in a homozygous AYAY individual. None of the other answers are correct. The AY allele lacks an upstream merc gene which is required for normal embryonic development. The AY allele contains a null mutation in the A gene, which is required for normal embryonic development. The yellow pigment produced by A allele is required for survival.

Human Biology (MindTap Course List)

11th Edition

ISBN:9781305112100

Author:Cecie Starr, Beverly McMillan

Publisher:Cecie Starr, Beverly McMillan

Chapter19: Introduction To Genetics

Section: Chapter Questions

Problem 9CT

See similar textbooks

Similar questions

In humans, the genetic disease cystic fibrosis is caused by a recessive allele (a). The normal (healthy) allele is dominant (A). What is the genotype of someone who has cystic fibrosis? What are the two different genotypes that a healthy person could have? If two people were both heterozygous for the cystic fibrosis gene, what fraction of their children would be likely to have this disease? Hint: Draw a Punnett square to figure it out.
In mice, the A allele causes agouti fur, the AY allele causes yellow fur and is dominant to the A allele. The homozygous AY AY genotype is lethal. Why is the AYAY homozygous condition lethal?
In mice, the wild-type coat color, agouti (AA) [left mouse], is dominant to solid-colored, black fur (aa) [middle mouse]. However, a separate gene (C) is necessary for pigment production. A mouse that is homozygous for a recessive c allele at this locus is unable to produce pigment and is albino [right mouse] regardless of the allele present at locus A. Thus, the following genotypes are listed with their associated phenotypes: ~ A/A; C/C or A/A; C/c or A/a; C/C or A/a; C/c ==> "agouti" ~ a/a; C/C or a/a; C/c ==> "black" ~ A/A; c/c or A/a; c/c or a/a; c/c or a/a; c/c ==> "albino" This is an example of recessive epistasis, in which the recessive c allele "stands upon" the possible genotypes for the A gene (A/A, A/a, or a/a). If two agouti mice with the A/a; C/c genotype are mated, what is the expected phenotypic ratio in their offspring? A.9 albino, 4 agouti, 3 black B. 9 agouti, 4 albino, 3 black C.9 black, 4 albino, 3 agouti D.9 agouti, 4 black, 3 albino
In humans, alkaptonuria is a metabolic disorder in which affected persons produce black urine. Alkaptonouria results from an allele (a) that is recessive to the allele for normal metabolism (A). Alana has a normal metabolism, but her brother has alkaptonouria. Alana’s father has alkaptonuria. Give the genotypes of Alana _______, her mother________, her father_______, and her brother______. If Alana’s parents have another child, what is the probability that the child will have alkaptonuria?_____ If Alana marries a man with alkatonuria, what is the probability that their first child will have black urine? _______ What is the probability that 3 of their children will have black urine?__________ If Alana marries a man that does not have alkatonuria, but has a mother that does, then what is the probability that their first child will have black urine? _______ 3 children in a row? ___________
In guinea pigs, an allele for rough fur (R) is dominant over an allele for smooth fur (r), and an allele for black coat (B) is dominant over an allele for white fur (b). What would be the genotype of a guinea pig with smooth black fur?
In genetics, the dash symbol (–) is a “wild card” that stands for either the dominant allele or the recessive allele; for example, A– means the individual has either the genotype AA or Aa. Two genes that undergo independent assortment affect coat color in Duroc pigs. Each gene has two alleles, one of which is dominant for coat color. Genotypes of the form A– B– are red, those of the form A– bb and aa B– are sandy, and genotype aa bb is white. What ratio of red:sandy:white is expected from the cross Aa Bb x Aa Bb?
In the hypothetical Spring Songbird, golden (G) is a Z-linked gene that controls wing color. The wild-type allele (G+), which codes for orange feathers, is completely dominant to the mutant allele (G), which codes for golden feathers. A male Spring Songbird with orange feathers could have which of the following genotypes? Z(G+) Z(G) ZIG+) W Z(G) Z(G) more than one of the answers listed here is correct ZIG) W Z(G+) Z(G+)
Skin color in humans is determined by polygenic inheritance, which means the more dominant alleles there are, the darker the skin color will be. A medium-toned skinned woman (AaBb) has a child with another medium-toned skinned man (AaBb). What is the probability of them having a very dark-toned skinned child? (Hint: the genotype is homozygous dominant)
The correct answer is : codominance and incomplete penetrance because in codominance, heterozygotes express both alleles equally, so heterozygotes will have two phenotypes, both visible. In incomplete penetrance, some individuals with a particular genotype have a phenotype that does not match their genotype. The ratio shown suggests that not all heterozygotes have the splotchy phenotype normally expected and instead have the dominant brown phenotype.
In some breeds of dogs, a dominant allele controls the characteristics of barking while trailing. In these dogs, another independent allele produces erect ears; it is dominant over the allele for drooping ears. Suppose a dog breeder wants to produce a pure-breeding strain of droop-eared barkers, but he knows that the genes for silent trailing and erect ears are present in his kennels, how would he proceed?
In mice, the A allele causes agouti fur, the AY allele causes yellow fur and is dominant to the A allele. The homozygous AY AY genotype is lethal. Why is the AYAY homozygous condition lethal? The AY allele lacks an upstream merc gene which is required for normal embryonic development. The AY allele contains a null mutation in the A gene, which is required for normal embryonic development. The yellow pigment produced by A allele is required for survival. The AY allele highly transcribes the merc gene which is lethal in a homozygous AYAY individual. None of the other answers are correct.
In mice, the presence of AA alleles give rise to the agouti fur color, AAY gives rise to a yellow fur color, and AYAY is lethal, causing mice to die before birth. The B allele results in pigment formation and is dominant over the b allele. The bb genotype results in no pigment formation and gives an albino fur color irrespectively of the presence of the AA or AAY alleles. In the following cross between a yellow and agouti mice, what would be the expected proportion of agouti fur mice among the live offspring? AAY Bb X AA Bb 1/2 1/4 3/8 1/3 3/4